textproduct: Quad Cities

KEY MESSAGES

- A Dense Fog Advisory has been extended until 12 PM Sunday along and north of I-80 in Iowa including also Rock Island and Jo Daviess Counties. A second dense fog advisory has been issued until 6 AM Sunday along and south of a line from Washington to Oakville Iowa and into Clark and Scotland Counties in Missouri.

- Widespread rain, with isolated thunder late tonight and Sunday. Small hail/gusty winds possible in strongest cells in west central IL and northeast MO.

- There is high probabilities (60-80%) of 45+ mph wind gusts Sunday afternoon and evening. A wind advisory has been issued for the entire area.

- Rapidly falling temperatures below freezing and a transition to snow showers expected late Sunday afternoon and evening. Slick roads will be possible. There is a 40-60% chance of 2"+ snow along and north of Hwy 20 by Monday morning.

UPDATE

Issued at 704 PM CST Sat Dec 27 2025

Observations and area road cameras have shown a drop in visibilities across eastern Iowa and far northeast Missouri this evening. Abundant low level moisture and surface winds are forecast to diminish to less than 5 knots this evening allowing areas of dense fog to develop across the area. Have expanded the Dense Fog Advisory for areas along and south of a line from Washington to Oakville Iowa and into Scotland and Clark County Missouri until 6 AM. Precipitation is forecast to develop early Sunday morning which should allow for some improvement in visibilties in this area Sunday morning.

SHORT TERM /THROUGH SUNDAY NIGHT/

Issued at 200 PM CST Sat Dec 27 2025

Low clouds and persistent dense fog was seen today, thanks in part to a very strong inversion at 960mb per our 18z DVN sounding. Above this inversion, temperatures have warmed 4.5C to 13.6C at 850mb since our 00z sounding last evening. Because of this inversion and the increasing warm moist advection in vicinity of a lifting warm front, have extended the dense fog advisory through Noon Sunday for areas along and north of I-80 in Iowa. Some brief improvements may be seen, but expect further reductions in visibility after sunset tonight. A further expansion south may also be needed this evening and will let the evening shift monitor trends for this. With such a moist boundary layer, temperatures have not risen much throughout the day with readings in the upper 30s/low 40s.

Tonight/early Sunday...steady or slowly rising temperatures are forecast as a surface low analyzed in southeast NE near Beatrice lifts east northeast into Iowa. Increasing low level convergence will result in rain overspreading in the area. In addition, RAP 700-500mb theta-e lapse rates and MUCAPE progs continue to support a few rumbles of thunder in our far south in northeast MO and west central IL, with a very low risk of small hail and gusty winds in the strongest cells prior to 10am. Models show a substantial increase in moisture (evident by PWs rising to 1 to 1.3" or near the monthly max for December for DVN) combined with the large scale forcing will support widespread 0.40" to 0.60" rain amounts highest east of MS RVR aiding in some drought relief.

Attention then turns to the strong cold front progged to move through Sunday afternoon and the strengthening winds and falling temps. Forecast soundings continue to show very strong winds (45kts at top of mixed layer) and combined with the deepening surface low (5-9mb 3-hr pressure rises per the NAM) will yield 25-35 mph sustained winds with gusts up to 50 mph. For these reasons, have issued a wind advisory for the entire CWA Sunday afternoon through Monday evening. If that were not enough, the 12z HREF ensemble max probs show even higher gusts approaching high wind criteria north of Hwy 30 that will need to be monitored.

Winter Impacts

Sharply falling temperatures from the 50s/40s to the 20s/teens is expected Sunday afternoon and evening. Thermal profiles show a quick changeover to snow from west to east and any lingering moisture freezing on untreated roads to hazardous travel. Iowa DOT pavement temperature forecasts quickly go below freezing after 5 pm. While better forcing for deformation snow will be further to the north late Sunday, some accumulation on untreated roads and surfaces will be possible north of Hwy 30. More information on totals can be found in long term section.

LONG TERM /MONDAY THROUGH SATURDAY/

Issued at 200 PM CST Sat Dec 27 2025

Monday...strong cyclonic flow aloft to bring us back to winter across the area. Strong forcing and lingering moisture on the back side of the deepening surface low to keep deformation snow showers going through at least mid-day. NBM probabilities for 2"+ have increased in previous runs into the 40-60% range now primarily along and north of Hwy 20, with a sharp gradient to no snow on the southern edge. Total snowfall amounts will be difficult to measure with this event, with strong northwest winds. In addition, these winds may bring periods of lower visibility in the snow showers creating hazardous travel conditions. A winter weather headline may be needed for a portion of the area.

Tuesday-Saturday...starting to see more consensus toward a northwest flow pattern. This would support staying colder, near normal, and would favor clipper systems that are difficult to pin down specific details at this time range. At this time, there is one potentially impacting the are for New Year's Eve into New Year's Day with rain/snow depending on the track and another system late next weekend.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 529 PM CST Sat Dec 27 2025

TAFs continue to range from IFR to LIFR across the area early this evening with fog and low clouds across the region ahead of a strong storm system that is forecast to move across the area late tonight through the day on Sunday.

Ceilings:

Still expecting widespread IFR to LIFR ceilings across the area this evening with periods of VLIFR as fog settles in across the area. VLIFR conditions will prevail in areas that see dense fog with ceilings lifting IFR first at KBRL as precipitation spreads into the area between 9 and 12 UTC. Ceilings will lift to IFR area wide as precipitation spreads northward across the area through 15 UTC Sunday.

Visibility:

Visibility is expected to deteriorate this evening area wide as fog redevelops across the area with visibility between a quarter and a half mile. Visibility is expected to improve first at KBRL as -SHRA moves into the area between 9 to 12 UTC from south to north. Mainly MVFR visibility is expected in rain. Visibilities may drop to IFR in heavier precipitation and as SN mixes in at all TAF sites after 20 UTC.

Precipitation:

Precipitation is expected to begin as all rain as the storm system moves into the area. Then a strong cold front is forecast to move across the area after 15 UTC on Sunday and switch winds from southerly to northwesterly behind the front. Precipitation may be a mix of RASNPL by 20 UTC before a transition to all SN potentially in the 22 to 00 UTC window.

Winds:

Winds are expected to turn to the south overnight with speeds at 5 knots or less through 9 UTC Sunday. Winds will begin to increase as a strong cold front moves into the area after 12 UTC Sunday with winds increasing to 10 to 20 knots during the afternoon with gusts up to 30 knots and wind shift to the northwest by 21 UTC. Wind gusts will approach 40 knots by the end of the TAF period.

DVN WATCHES/WARNINGS/ADVISORIES

IA...Dense Fog Advisory until noon CST Sunday for IAZ040>042- 051>054-063>068. Wind Advisory from 2 PM Sunday to 6 PM CST Monday for IAZ040>042-051>054-063>068-076>078-087>089-098-099. Dense Fog Advisory until 6 AM CST Sunday for IAZ076>078- 087>089-098-099. IL...Dense Fog Advisory until noon CST Sunday for ILZ001-015. Wind Advisory from 2 PM Sunday to 6 PM CST Monday for ILZ001- 002-007-009-015>018-024>026-034-035. MO...Wind Advisory from 2 PM Sunday to 6 PM CST Monday for MOZ009- 010. Dense Fog Advisory until 6 AM CST Sunday for MOZ009-010.